She's singing lullabies for her son John. He was born 16 weeks early. Rachel, "And he weighed one pound eight ounces."

Rachel Shrier, John's mother, says: "The way I feel about you is a kind of song."

This could train him to eat. Vanderbilt University doctor Nathalie Maitre says the problem with preemies is ... "they don't know how to suck to get food, to swallow that food, and to breathe while you're swallowing it."

She believes moms' voices can be the motivation needed. Rachel sings, "Snuggle puppy of mine."

Rachel's songs are plugged into a special pacifier device.

Dr. Maitre, "If the baby is sucking at the right rhythm and strength, it plays mom's voice singing."

Rachel sings, "I love what you are."But if John doesn't do it right, the singing stops.

Rachel, "He can correlate the sucking with hearing my voice."

A new study shows premature babies who received the therapy 15 minutes a day for five consecutive days, ate faster and went home up to 14 days sooner than other preemies.

Dr. Maitre, "They grow better and then they're at much less risk of infection."

Rachel hopes it will help her baby boy too.

Rachel sings, "Oooo, I love you."

I'm Lou Baxter reporting.

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